“…There have been reports on the application of porphyrin metal complexes (Figures 24, 25) for the detection of other anions like Cl - [88-90] Br - [91-93], I - [93-95], I 3- [96], arsenite [97], SCN - [98, 83], dinitro benzoate [99], histidin [100], nitrite [101], NO 3 - [102]. …”